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1.
对鞍钢股份无缝钢管厂连轧机前毛管坯横移装置存在的设计缺陷进行了分析,并提出改进方案,将原横移装置由高架轨道横移机构及上下升降链传动装置,改进为地面轨道横移系统及同步旋转臂实现取管、放管过程。实施后消除了生产故障,缩短了轧制周期,降低生产成本。 相似文献
2.
循环神经网络(RecurrentNeuralNetworks)是人工神经网络(ArtificialNeuralNetworks)中重要的分支,与前馈神经网络(ForwardNeuralNetworks)相比具有更好的时间序列学习能力。但长期以来其学习法一直不能脱离前馈神经网络而自成一体,回声状态神经网络(EchoStateNetworks(ESN))是打破这一局面的全新学习方法。其独特的结构,良好的短期记忆能力,方便的学习方法,不俗的非线性特性是以前循环神经网络所不可比的。本文在介绍了回声状态神经网络之后将其用于四轮机器人的位置测量系统中,有良好的表现。 相似文献
3.
J. Giacomin M. S. Shayaa E. Dormegnie L. Richard 《International Journal of Industrial Ergonomics》2004,33(6):56-541
The human perception of rotational hand–arm vibration has been investigated by means of a test rig consisting of a rigid frame, an electrodynamic shaker unit, a rigid steering wheel, a shaft assembly, bearings and an automobile seat. Fifteen subjects were tested while seated in a driving posture. Four equal sensation tests and one annoyance threshold test were performed using sinusoidal excitation at 18 frequencies in the range from 3 to 315 Hz. In order to guarantee the generality of the equal sensation data, the four tests were defined to permit checks of the possible influence of three factors: reference signal amplitude, psychophysical test procedure and temporary threshold shift caused by the test exposure. All equal sensation tests used a reference sinusoid of 63 Hz at either 1.0 or 1.5 m/s2 r.m.s. in amplitude. The four equal sensation curves were similar in shape and suggested a decrease in human sensitivity to hand–arm rotational vibration with increasing frequency. The slopes of the equal sensation curves changed at transition points of approximately 6.3 and 63 Hz. A frequency weighting, called Ws, was developed for the purpose of evaluating steering wheel rotational vibration. The proposed Ws has a slope of 0 dB per octave over the frequency range from 3 to 6.3 Hz, a slope of −6 dB per octave from 6.3 to 50 Hz, a slope of 0 dB per octave from 50 to 160 Hz and a slope of −10 dB per octave from 160 to 315 Hz. Ws provides a possible alternative to the existing Wh frequency weighting defined in International Standards Organisation 5349-1 (2001) and British Standards Institution BS 6842 (1987).
Relevance to industry
For the manufacturers of tyres, steering systems and other vehicular components the proposed Ws frequency weighting provides a more accurate representation of human perception of steering wheel rotational vibration than the Wh weighting of ISO 5349-1 and BS6842. 相似文献
4.
本文利用可控平均冷却速度的单向凝固实验炉测定了45号钢在不同平均冷却速度下的冷却曲线,由此得到其在凝固期间的平均冷却速度R,相应地测量了不同平均冷却速度下试样的二次枝晶臂间距S2,通过回归,得到了如下关系式:S2=727R-0.41,并将引式成功地应用于实际生产中。 相似文献
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针对现有掘进机多采用单一的横轴式或者纵轴式整机,对不同岩层掘进工作的适应能力差等问题,提出一种面向不同岩层的掘进机截割臂互换性设计方案。对纵、横轴式2种掘进机的结构特点与性能进行了对比分析;针对2种截割臂工作模式的特点,分别设计了相应的截割减速器。Solidworks仿真结果表明,与单一横轴式或者纵轴式掘进机相比,采用互换式截割臂结构可有效提高掘进机对不同岩层截割工作的适应能力,提高掘进效率,节省设备运输及使用成本。 相似文献
8.
In this paper, the authors address the problem of edge-perception for its applications to vision-feedback control in robotic systems.In natural vision, the recognition of objects takes place through the process consisting of eye system, neural networks and cognition. The cognitive process, in turn yields a phenomenon known as perception. This is the phenomenon of perception of physical attributes, such as edges, color and texture, etc., which is responsible for the recognition of objects through the natural vision processes.In this paper, we make an attempt to postulate the theory of perception for gray-level images. The gray-level images, when going through the cognitive and perception processes, are contaminated by the uncertainty; here we call it cognitive uncertainty.The studies in this paper are confined to the phenomenon of edge-perception for two-dimensional gray-level images, however, these studies can be extended to other types of visual attributes both in two-dimensional and three-dimensional spaces. Indeed, the perception of these attributes, which attempts to emulate the human vision system, may help in the design of a truly robust computer vision-feedback control system for robotic applications. 相似文献
9.
基于偏差向量的机器人装配系统零件抓取精度分析 总被引:2,自引:0,他引:2
应用偏差向量描述了影响机器人抓取零件过程的各种误差,提出了计算零件抓取成功性方法,在引入手爪的偏差矫正能力的概念后,建立了确定零件抓取精度的模型,该模型适合于各种零件抓取过程,是研究机器人装配系统的装配精度和装配质量的基础。 相似文献
10.
Due to the growing importance of width control in strip and plate mills, edge rolling is currently an im-portant process in
hot rolling mills. Research in edge rolling has been carried out, and in the present ar-ticle, models for roll force, torque,
and lever arm coefficient are derived using the upper bound method. A simple, kinematically admissible deformation zone and
velocity field, independent of friction in the roll gap, is proposed, and the energy dissipation rate is derived. The formula
for energy dissipation rate has, in practice, no limitation because all edge rolling geometries are safely in the area where
the formula is valid. Roll force and torque are derived by means of two independent integrals. Thus, the lever arm coef-ficient
is evaluated from the expressions for roll force and torque using conventional rolling theory. Roll-ing trials report good
agreement with theory. Measured roll forces are similar to calculated forces. Furthermore, the shape of the dogbone that arises
during edge rolling is in fairly good agreement with the calculated dogbone shape. Deviations are due to the deviation from
ideally plastic material in the ex-periments. Also, the strain distribution over the dogbone is similar to the proposed deformation
zone. Thus, a new formula has been developed to a stage that it can be implemented in width control systems for edge rolling
stands in hot strip and plate mills. 相似文献